This commit is contained in:
eric
2026-03-31 11:27:39 -05:00
parent d16f188845
commit 80a4b2d0f9
5 changed files with 33 additions and 16 deletions

View File

@@ -43,24 +43,36 @@ def aes_decrypt_base64(cipher_b64: str, encoding_aes_key: str) -> str:
cipher = AES.new(aes_key, AES.MODE_CBC, iv)
decrypted = cipher.decrypt(cipher_bytes)
decrypted = pkcs5_unpadding(decrypted)
# 微信消息体格式16B随机串 + 4B网络序长度 + 明文 + appid
if len(decrypted) < 20:
raise ValueError("解密后消息长度非法")
content = decrypted[16:]
msg_len = struct.unpack("!I", content[:4])[0]
msg_start = 4
msg_end = msg_start + msg_len
if msg_end > len(content):
raise ValueError("解密后消息长度字段越界")
msg = content[msg_start:msg_end]
return msg.decode("utf-8")
# 兼容两种格式:
# 1) 微信消息体16B随机串 + 4B长度 + 明文 + appid
# 2) 纯文本:直接是明文 JSON/XML
try:
if len(decrypted) < 20:
raise ValueError("payload too short")
content = decrypted[16:]
msg_len = struct.unpack("!I", content[:4])[0]
msg_start = 4
msg_end = msg_start + msg_len
if msg_end > len(content):
raise ValueError("msg length out of range")
msg = content[msg_start:msg_end]
text = msg.decode("utf-8")
if text:
return text
except Exception:
pass
return decrypted.decode("utf-8")
def aes_encrypt_base64(plaintext: str, encoding_aes_key: str, app_id: str) -> str:
def aes_encrypt_base64(plaintext: str, encoding_aes_key: str, app_id: str | None = None) -> str:
aes_key, iv = get_aes_key_and_iv(encoding_aes_key)
raw = plaintext.encode("utf-8")
# 微信消息体格式16B随机串 + 4B网络序长度 + 明文 + appid
data = os.urandom(16) + struct.pack("!I", len(raw)) + raw + app_id.encode("utf-8")
if app_id:
# 微信消息体格式16B随机串 + 4B网络序长度 + 明文 + appid
data = os.urandom(16) + struct.pack("!I", len(raw)) + raw + app_id.encode("utf-8")
else:
# 纯明文格式
data = raw
padded = pkcs5_padding(data)
cipher = AES.new(aes_key, AES.MODE_CBC, iv)
encrypted = cipher.encrypt(padded)